Show variant on the website

On my website, I cannot access the configuration of the variations of a model. I don’t think I have flag problems, I’ve checked them all several times, it’s like the “configure button” does not perform any action.
This problem applies to all variant models. I checked the settings of the site, models, variants, etc etc
Here is an example
http://termoidraulicarusso.it/prodotti/centrali-termiche/centraline/adattatori/kit-far-x-multistrato-classico-kfm

Hello,

Which version of Frappe and ERPNext are you using?

ERPNext: v12.13.0 (version-12) -Frappe Framework: v12.11.0 (version-12)
but it is not a question of version even with 12.5 and 12.3 it behaved in the same way. In fact, I thought it was an update proposal, then I realized I had some compromised files that I fixed. Now it seems that the configuration button link to the variant templates is missing.